Crohn’s Disease (CD) is one of the two common types of IBD (inflammatory bowel disease). While digestive issues are well-known in CD, the impact of systemic inflammation can extend beyond the gut.
These symptoms are called extraintestinal manifestations (EIMs) and are experienced by up to 50% of patients, with skin symptoms being the most common. This post will explore the connection between CD and skin problems and provide research-backed treatments and solutions recommended by experts.
The Connection Between CD & Skin Conditions
Although the connection between IBD and skin diseases is not fully understood, researchers have discovered a bidirectional relationship between the gut microbiome and skin health. This relationship is called the Gut-Skin Axis.
The gut microbiome contains bacteria, viruses, protozoa, and fungi that maintain a symbiotic relationship with the body. They are affected by factors such as age, environment, and diet, which in turn affect the skin.
An example of food in the gut affecting the skin is someone eating a food they are allergic to, which causes them to break out in hives. Inversely, the skin can also affect the gut, such as the increased diversity of the gut microbiome after one’s exposure to the ultraviolet rays of the sun.
Types of Skin Conditions in Crohn’s Disease
Approximately 15-20% of patients with IBD have skin EIMs. Skin EIMs can be divided into four categories:
Reactive EIMs: These share similar immune system triggers with IBD, but the skin doesn’t show the same damage as the gut. Examples include erythema nodosum (painful bumps), pyoderma gangrenosum (sores), and mouth ulcers.
Specific EIMs: These skin problems mimic the damage seen in the gut but appear outside the digestive tract.
Associated EIMs: These are skin conditions like psoriasis or eczema that are more common in IBD, but not directly caused by it. This hints at underlying risk factors that are not yet understood.
Complications: These skin issues can be caused by the IBD itself or by medications used to treat it.
Erythema Nodosum (EN)
EN is the most prevalent skin disorder in IBD patients and is seen more frequently in CD than in UC. It is characterized by the appearance of red, painful nodules – typically on the shins although they can appear on other areas like the arms, thighs, or torso.
To alleviate symptoms of EN, you can elevate your legs and wear compression stockings or bandages. If the EN is more serious, speak with your doctor about oral steroids which can quickly resolve the painful lesions.
Pyoderma Gangrenosum (PG)
PG is the second-most prevalent skin disorder in IBD patients, and it is the most serious. The patient develops painful ulcers on the skin of their body – typically on their legs. Depending on the stage and severity, IV steroids or creams may be used to treat the ulcers.
Sweet Syndrome (SS)
Patients with SS experience a sudden onset of red or purplish bumps on their bodies, accompanied by fever, headache, joint pain, and fatigue. SS typically follows symptoms of intestinal inflammation in IBD, so if, for example, a patient has a CD flare-up, SS bumps may begin to appear on the skin.
Oral or IV steroids have a 90% success rate in treating patients with SS, and a biologic drug may be considered if the patient is unable to tolerate steroids.
Psoriasis
Those with Crohn’s disease or colitis have an increased risk of developing psoriasis compared to the general population. Psoriasis is a condition that causes an increase in the production of skin cells. This causes dry, itchy, or scaly patches of discolored skin. There is a heightened risk of skin infections during a psoriasis flare.
Treatment for milder cases of psoriasis may involve corticosteroid topical creams or ointments, Retinoid gel, or light therapy. More severe cases may require oral or injected medications such as steroids, Retinoids, biologics, methotrexate, or immune suppressants.
When to Seek Medical Advice
If you have Crohn’s Disease and have noticed the appearance of a rash on your skin, it’s best to consult with your doctor immediately for assessment. Early intervention through managing your CD inflammation and taking steroids under the medical guidance of your doctor has been shown in the cited research to be effective.
It is important to note that not all EIMs are due to IBD—they may be caused or worsened by IBD treatments, therefore a pause in treatment should be considered to rule out whether the EIMs are drug-related or are caused by CD.
Keren Oren
